I have a function defined as follows:

public class RegistrationFunction(
    IUserExistsQuery userExistsQuery,
    IRegisterUserCommand registerUser)
{
    [Function(nameof(RegistrationFunction))]
    [OpenApiOperation(operationId: "RegisterUser", Visibility = OpenApiVisibilityType.Important)]
    [OpenApiSecurity("function_key", SecuritySchemeType.ApiKey, Name = "x-functions-key", In = OpenApiSecurityLocationType.Header)]
    [OpenApiRequestBody(contentType: MediaTypeNames.Application.Json, bodyType: typeof(UserDataRequestBody))]
    [OpenApiResponseWithoutBody(statusCode: HttpStatusCode.OK)]
    [OpenApiResponseWithoutBody(statusCode: HttpStatusCode.Conflict)]
    [OpenApiResponseWithBody(statusCode: HttpStatusCode.BadRequest, bodyType: typeof(RegistrationErrorResponseBody), contentType: MediaTypeNames.Application.Json)]
    public async Task<HttpResponseData> Run(
        [HttpTrigger(AuthorizationLevel.Function, "post")] HttpRequestData req,
        [FromBody] UserDataRequestBody userData)
    {
        // code removed for brevity
    }
}

I’m also using the right package reference to enable OpenApi docs:

<PackageReference Include="Microsoft.Azure.WebJobs.Extensions.OpenApi" Version="1.5.1" />

And my Program.cs contains this code, which I also think is correct:

var host = new HostBuilder()
    .UseServiceProviderFactory(new AutofacServiceProviderFactory())
    .ConfigureContainer<ContainerBuilder>(builder =>
    {
        builder.RegisterType<UserExistsQuery>().AsImplementedInterfaces().SingleInstance();
        builder.RegisterType<RegisterUserCommand>().AsImplementedInterfaces().SingleInstance();
    })
    .ConfigureServices(services =>
    {
        services.AddDbContext<MLTRContext>(options =>
        {
            var connectionString = Environment.GetEnvironmentVariable("PostgresConnectionString");
            
            options.UseNpgsql(connectionString);
        });
        services.AddSingleton<IOpenApiConfigurationOptions>(_ =>
        {
            var options = new OpenApiConfigurationOptions
            {
                Info = new OpenApiInfo
                {
                    Version = DefaultOpenApiConfigurationOptions.GetOpenApiDocVersion(),
                    Title = $"{DefaultOpenApiConfigurationOptions.GetOpenApiDocTitle()} (Injected)",
                    Description = DefaultOpenApiConfigurationOptions.GetOpenApiDocDescription(),
                    TermsOfService = new Uri("https://github.com/Azure/azure-functions-openapi-extension"),
                    Contact = new OpenApiContact
                    {
                        Name = "Enquiry",
                        Email = "[email protected]",
                        Url = new Uri("https://github.com/Azure/azure-functions-openapi-extension/issues"),
                    },
                    License = new OpenApiLicense
                    {
                        Name = "MIT",
                        Url = new Uri("http://opensource.org/licenses/MIT"),
                    }
                },
                Servers = DefaultOpenApiConfigurationOptions.GetHostNames(),
                OpenApiVersion = DefaultOpenApiConfigurationOptions.GetOpenApiVersion(),
                IncludeRequestingHostName = DefaultOpenApiConfigurationOptions.IsFunctionsRuntimeEnvironmentDevelopment(),
                ForceHttps = DefaultOpenApiConfigurationOptions.IsHttpsForced(),
                ForceHttp = DefaultOpenApiConfigurationOptions.IsHttpForced(),
            };

            return options;
        });
    })
    .ConfigureFunctionsWorkerDefaults(w => 
        w
            .UseMiddleware<ErrorExposingMiddleware>()
            .UseMiddleware<PrintEnvVarsMiddleware>())
    .Build();

await host.RunAsync();

However, when I build and run the code locally, no OpenApi endpoints appear in the console, and if I try going to /api/swagger/ui, I get 404. May it be because my code layout is a little bit non-standard?

| - Program.cs
| - local.settings.json
| | - Functions
| | | - Registration
| | | | - RegistrationFunction.cs